
<A NAME=ASIN>

<TITLE>ASIN</TITLE></A>
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<B>ASIN</B> _ _ _  _ _ _  _ _ _  _ _ _ <B>operator</B><P>
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The <em>asin</em> operator returns the arcsine of its argument. 
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syntax: </H3>
<em>asin</em>(&lt;expression&gt;) or <em>asin</em> &lt;simple\_expression&gt; 
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&lt;expression&gt; may be any scalar REDUCE expression, not an array, matrix or 

vector expression. &lt;simple\_expression&gt; must be a single identifier or 
begin with a prefix operator name. 
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examples: </H3>
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asin(givenangle); 

  ASIN(GIVENANGLE) 


asin(5); 

  ASIN(5) 


df(asin(2*x),x); 

                 2
    2*SQRT( - 4*X  + 1))
  - -------------------- 
             2
          4*X  - 1


on rounded; 

asin .5; 

  0.523598775598 


asin(sqrt(3)); 

  ASIN(1.73205080757) 


asin(sqrt(3)/2); 

  1.04719755120 

</TT></PRE><P>A numeric value is not returned by <em>asin</em> unless the switch
 
<em>rounded</em> is on and its argument has an absolute value less than or 
equal to 1. 
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